The polysaccharides of Astragalus membranaceus have received extensive study and attention, but there have been few reports on the extraction of these polysaccharides using cold water (4 °C). In this study, we fractionated a novel cold-water-soluble polysaccharide (cAMPs-1A) from Astragalus membranaceus with a 92.00% carbohydrate content using a DEAE-cellulose 52 anion exchange column and a Sephadex G-100 column. Our UV, Fourier-transform infrared spectroscopy (FTIR), high-performance gel permeation chromatography, and ion chromatography analysis results indicated the monosaccharide composition of cAMPs-1A with 1.23 × 10⁴ Da molecular weight to be fucose, arabinose, galactose, glucose, and xylose, with molar ratios of 0.01:0.06:0.20:1.00:0.06, respectively. The UV spectroscopy detected no protein and nucleic acid in cAMPs-1A. We used FTIR analysis to characterize the α-d-pyranoid configuration in cAMPs-1A. In addition, we performed animal experiments in vivo to evaluate the antitumor and immunomodulatory effects of cAMPs-1A. The results suggested that cAMPs-1A oral administration could significantly inhibit tumor growth with the inhibitory rate of 20.53%, 36.50% and 44.49%, respectively, at the dosage of 75,150, and 300 mg/kg. Moreover, cAMPs-1A treatment could also effectively protect the immune organs, promote macrophage pinocytosis, and improve the percentages of lymphocyte subsets in the peripheral blood of tumor-bearing mice. These findings demonstrate that the polysaccharide cAMPs-1A has an underlying application as natural antitumor agents.

Dihydroquercetin is a kind of dihydroflavonol compounds with antioxidant, antitumor, antivirus and radioresistance activities. This study attempted to produce the dihydroquercetin complexes with lecithin and β-cyclodextrin, and research their characteristics and bioactivities via ultraviolet spectrum (UV), infrared spectroscopy (IR), scanning electron microscope (SEM), differential scanning calorimetry (DSC), X-ray diffraction spectrum (XRD), and MTT assay. Results showed that the complexes with lecithin and β-cyclodextrin could improve the solubility and dissolution rate, and remove the characteristic endothermic peak of dihydroquercetin. IR spectra proved their interaction, and results of SEM and XRD showed the amorphous characteristics of the dihydroquercetin compounds. These results indicated that dihydroquercetin was combined by lecithin or β-cyclodextrin with better physical and chemical properties, which would effectively improve the application value in the food and drug industries.

In this study, the polysaccharides (PPs) from pomelo peels were investigated for their structural characteristics and antitumor mechanism on sarcoma S180-bearing mice. Components, FT-IR, and GC analysis showed that PPs, mainly composed of glucose, were typical acid polysaccharides with α-d-pyranoid glucose containing 74.52% carbohydrate and 16.33% uronic acid. The in vivo antitumor tests revealed that PPs could effectively suppress the transplanted S180 tumors growth, as well as protect the immune organs, improve proliferation ability of splenic lymphocytes and killing activity of NK cells in tumor-bearing mice. Furthermore, the levels of serum cytokines (IL-2, IFN-γ and TNF-α) and the proportion of CD4⁺ T cells in peripheral blood of mice bearing S180 tumors were also significantly increased after treatment with PPs. Meanwhile, the transplanted S180 tumor cells exhibited obvious apoptotic phenotype after PPs treatment by arresting the cell cycle in S phase, down-regulating the Bcl-2 expressions and up-regulating the Bax levels. These data showed that PPs were mainly composed of glucose with α-d-pyranoid ring and could induce apoptosis of solid tumor cells by enhancing the antitumor immunity of tumor-bearing mice, which would provide a theoretical basis for the practical application in food and medical industries.

Ethanol fractional precipitation can initially separate polysaccharides according to the structure, which exhibits strong correlation with the biological activities. This study aimed to investigate the impact of varying ethanol concentrations on the structural characteristics, and the antitumor and antioxidant activities of polysaccharides derived from Dendrobium officinale through ethanol fractional precipitation, as well as their internal relationships. The polysaccharides acquired by absolute alcohol additions at a final liquor-ethanol volume ratio of 1:1, 1:2, and 1:4 were named DOP-1, DOP-2, and DOP-4, and the supernatant was named DOP-S. The results of the structural analysis revealed that the increase in ethanol concentrations resulted in a reduction in the molecular weights and the acetylation degree of the polysaccharides, as well as a decrease in mannose content and an increase in glucose content. In vitro experiments demonstrated that DOP-S exhibited optimal antitumor and antioxidant activities. Animal experiments further confirmed that DOP-S suppressed the growth of solid tumors significantly, enhanced lymphocytes, mediated immune ability, and improved the activity of antioxidant enzymes. These findings would establish a theoretical foundation and provide technical support for further advances and applications of polysaccharides derived from D. officinale in the fields of food and medicine.

Degeneration of immune organs like thymus and spleen has been discovered in tumor-bearing mice; which increases the difficulties on oncotherapy. More effective drugs which target the protection of immune organs are expected to be researched. In this study; we aim to analyze the antitumor and immunoregulatory activities of seleno-β-lactoglobulin (Se-β-lg) on S180 tumor-bearing mice. Results indicated that Se-β-lg exhibited a remarkable inhibitory effect on S180 solid tumors with the inhibition rate of 48.38%; and protected the thymuses and spleens of S180-bearing mice. In addition, Se-β-lg could also balance the proportions of CD4⁺ and CD8⁺ T cells in spleens; thymuses and peripheral bloods; and improve Levels of IL-2; IFN-γ; TNF-α in mice serums. β-lg showed weaker bioactivities while SeO₂ showed stronger toxicity on mice. Therefore our results demonstrated that Se-β-lg possessed stronger antitumor and immunoregulatory activities with lower side effects and had the potential to be a novel immunopotentiator and antitumor agent.